Non-ash containing lubricating oil compositions



United States Patent NON-ASH This invention relates to improved lubricating oil compositions possessing multifunctional properties. More particularly the invention relates to mineral lubricating oils useful in the lubrication of engines operating over wide temperature ranges and under extreme pressures and other adverse conditions.

It is known that lubricating oils containing certain metallic salts or soaps such as metal sulfonates possess good dispersing and detergent properties. Such lubricants, however, tend to form metallic deposits in engine parts which interfere with the eifective operation of the engine. As a result, recent trends in this field have been to the use of non-ash forming basic and essentially neutral nitrogen-containing dispersants of high molecular weight such as copolymers of polymerizable amines or amides with long-chain acrylate esters and available commercially under the trade names of LOA-564 or 565, Acryloid 315X, 917 or 966 or certain rather high molecular weight amines, amides and/or imines derivatives of high molecular weight alkenyl maleic anhydride or the like. These non-ash forming nitrogen-containing compounds are ex-.

cellent detergents but under extreme pressure conditions exhibit a lack of stability and wear inhibiting properties and are non-resistant in combating sludge and corrosion.

Attempts to overcome the deficiencies of these polymeric,

detergent materials either by modifying the polymers or using auxiliary additives has met with little success. In most cases the auxiliary additives which appear to -be promising stabilizers and wear inhibitors are metal-containing compounds such as metal sulfonates or metal carboxylates and these are to be avoided for reasons stated. Also these materials tendto complex and form sludge.

It is an object of the present invention to provide an improved non-ash forming lubricating oil composition. It is another object of the invention to provide an improved detergent lubricant possessing good stability and antiwear properties. Still another object of the invention is to provide a corrosion and sludge resistant non-ash containing or forming lubricating oil composition. Other objects will become apparent during the following description of the invention.

Now in accordance with the present invention, it has been found that stability, as well as sludge, Wear and corrosion inhibiting properties can be imparted to lubricating oils by incorporating thereon small amounts of each of certain non-ash forming nitrogen-containing detergents selected from the group consisting of (I) (A) an oil-soluble amino-imide of a long-chain monosubstituted polymeric hydrocarbyl succinic anhydride and (B) full or partial amino-amides or polyamine salts of long-chain monosubstituted polymeric hydrocarbyl succinic anhydride and (II) oil-soluble bisphenols. To this additive combination of (I) and (II) can be incorporated (HI) partial or full esters of organic phosphates, phosphites,

phosphonates, phosphonites and their thio derivatives. In

compounds of (I) by long-chain hydrocarbyl is meant an olefinic polymer straight or branch chain and derived from olefins of from 2 to 8 carbon atoms such as ethylene, propylene, l-butene, isobutene, l-hexene, styrenes, and copolymers thereof, from 20 to 500 carbon atoms and a molecular weight of 300 to 5000, preferably from 800 to 1500.

It is surprising to find that the bisphenols which will be hereinbelow fully described, and which are known for their antioxidant properties should in combination with the detergents of this invention impart to them properties not exhibited by the bisphenols when used along or when also aided by he presence of esters of phosphorus as described.

The olefinic polymer present as an oil-solubilizing substituent and detergent aid of the nitrogen-containing compounds of the present invention may be prepared by any known means provided it is within the molecular weight' range indicated above. Examples of such polymers include polyethylene, polypropylene, polybutene, polyisobutylene, copolymer of ethylene/ propylene, copolymer of ethylene/ isobutylene, copolymer of ethylene/a-methylstyrene and the like. Monoalkylation of maleic anhydride with the above type olefinic polymers may also be made by conventional means known in the art, preferably in the absence of a catalyst and at temperatures ranging from about 300 F. to 600 F., preferably between 350 F. and 450 F. The mole ratio of the polyolefin to maleic anhydride may vary from 1:1 to 1:10, preferably from 1:1 to 1:5 respectively.

The amines used to form the compounds of (I) (A) namely the succinimides of the compounds or (I) (B), namely the full or partial amides or amine salts of the monosubstituted polymeric hydrocarbyl succinic anhydride can be represented by the formula where the R s can be hydrogen or the same or different C alkyl and/or aryl radicals and R is an alkylene radical of from 1 to 8, preferably 1 to 4 carbon atoms. Examples of such amines are alkylene polyamines such as ethylene diamine, diethylene triamine, triethylene tetramine, l-methyl ethylene diamine, l-ethyl ethylene diamine, propylene diamine, butylene diamine, trimethyl trimethylene diamine, tetramethylene diamine, diaminopentane or pentamethylene diamine, diaminohexane, hexamethylene diamine, heptarnethylene diamine, diamino-octane, decamethylene diamine, and the higher homologues up to 18 carbon atoms, phenylene diamine,

, (1,2,2 trimethylethylene)tetramine; di-(l methylamylene)triamine; tetra-(1,3 dimethylpropylene)pentamine; penta-(1,5-dimethylamylene)hexamine; di-(l methyl-4- ethylbutylene)triamine; penta-( 1,2-dimethyl-1-isopropyl ethylene)hexamine; tetraoctylenepentamine and the like.

The polyalkylenepolyamines can be prepared by several methods well known to the art. One well accepted method comprises reacting ammonia With an alkyl, or substituted alkyl, dihalide. For example, tetraethylenepentamine has been prepared by reacting ammonia with ethylene bromide. The preferred polyamines are the ethylene amines such as ethylene diamine, diethylene triamine, triethylene tetramine, tetraethylene pentamine, N-dimethyl aminopropylamine, N-dimethylaminobutylamine, N-diethylaminopropylamine, methylpropylaminoamylamine.

In forming the second stage of the reaction using the polyamines control of the mole ratio of the monopolyolefinic succinic anhydride and polyamine and the reaction temperature is important to obtaining desired end products of the (I) (A) or. (I) (B) type. The mole ratio of the (theory=.4% Infra-red analysis showed that the reaction product was an imide containing a polybutene side chain.

EXAMPLE III (TYPE (A) COMPOUND) polyamine to the anhydride compound can vary from 5 01:1 to 1:1 respectively. The. reaction temperature for A mixture f 213 gms. (0.21 mole) of dimethylaminoformation of c ompoundsq fl) (A) the succm1m1de s may propylamine and 150 gms (009 mol of the polybu Vary; E pieierably from to tenyl succinic anhydride of Example II hereinabove, was In the lormahhh of the Compounds (II (B) as blended with agitation in a nitrogen atmosphere, and the descnbhd f the tempfrature may Vary from 8 10 mixture was heated at 500 F. for a period of one hour, aftemherfmhe to about 300 Preferably from 100 ter which the absolute pressure was reduced to about 200 to 300 mm. Hg at this temperature during a period of 30 minutes lhyehhoh 1S Illustrated by j fohOWlhg examples to facilitate the removal of water and excess amine. The In which the Percentages are by Wfilghtreaction mixture was then allowed to reach room tem-. EXAMPLE I (TYPE (A) COMPOUND perature at this reduced pressure. The reaction product 750 f 1 b t 1 h 0 l 1 ht contained 1.7% nitrogen (theory=1.8% The identity 0 ggz g fi g i ggs g 3: 3 s ig g g fi of. the N-dirnethylaminopropylalkenyl succinimide was. a r l h and 30 gms. of maleic anhydride was added slowly over estab 1s ed by means of Infra red Spectroscopy a period of 30 minutes. The reactants were heated to 390 EXAMPLE IV (TYPE (B) COMPOUND)v F. to 400 F. and maintained at this temperature. for four hours and then heated to 440 F; and maintained at this holylsobuifylehe Succmlc ahhydnde R F h temperature for 16 hours. On cooling, the reactants were mg a polylsohuctylane M- and succmlc anhydrlde dissolved in 1.5 liters ofpetroleum spirit (60-80 c. B. P.) at atound Pl About 50hgmsand filtered. 19 gms. of tetraethylene pentamine was added pqlylsobqtylene succhhc hhhydnde h m was to the petroleum spirit solution. The petroleum spirit was hhxeh Wlth 50 of methylene mamme at distilled off and replaced by 1 liter of toluene which was amhlent temperahlw- The amlhe was added In lhcremehts also distilled off to azeotropically remove water, and the and the temperature colftroued so as not to use f residue was. heated. to 390 F. to 400 F. and maintained about reactwn proceeded for 15 t0 tthj temperature fo th hou utes after which the solvent was removed and the and.

v 7 product, a semi-amide of the above reactants, had anitro- EXAMPLE H gen-content of 1.6%. A mixture of 1000 grns. (1 mole) of a polybutene hav- Other examples of additives of the present invention ing a molecular weight of aboutv 1000 and 98 grns. (1 include:

Qlefin-Suceinic Anhydride Amine Mole Temp., Type of End-Product Ratio F.

V. P0lyisobuty1ene('M.W.850)-sueeinic Diethylamine 1/1 420 (A)-Imide.-

anhydride. propylamine. I I VI. Pol3"is0butylene (M .W. 8 Tetrae thylene 1.5/ 1"-.. 120 (B) Semi-amide.

snceinic anhydride. pentamine. 7 VII. Polyethylene/isohutylene (MW. Dimethylarnine 1/ 1. 450; (A) Imide.

1,000)-succinic anhydride. propylamine. VIII; Polyethylene/a-niethy1styrene Tetraethylene 1/1 450 Do.

(M.W. 800)-succi nic anhydride. pentamine IX. Pplyisobutylene (M.W. 1,000)- Tetraethylenau 1/1 120 (B) Amjne salt 0151013 succinic anhydride. isosuccinieanhy ride mole) of maleic anhydridewas heated'at 410"F, in a nitrogen atmosphere with agitation for a periodof- 24. hours. The reaction mixture wascooled; to 150 F. and. 700 cc. of hexane added; after whichthe; mixture was; filtered under vacuum. After vacuum. distillation to removethe hexane from the filtrate, the. productwas ,main: tained at 350 F. at an absolutepressure Qfi 10 mm. Hg for. one hour to remove traces of maleic anhydride. The crude. polybutenyl succinic anhydride t-husprepared had a saponi: fication number of 79.

EXAMPLE IIA.P R EPARATION OF 'TE'FRAETHYL- ENEPENTAMINE DERIVATIVE OF POLY BUTENYL SUCCIN-IC ANHYDRIDE OF EXAM- PLE IIHEREINABOVE (TYPE (A) COMPOUND) A mixture of 84 gms. (0.45 mol) of tetraethylene P61 tamirie and 702 gms. (0.45 mol.) of the pqlyhutenyl succinic anhydride of-ExampleII hereinabove, wasblended with agitationat 125 F. inanitrogen atmosphere The temperature Was increased to 400 F. during aperiod of one hour, after which the absolute. pressure was reduced to about 200 mm. Hg during a period of 30 minutesto facilitate the removal of water. The reactionmixture was then allowed to .reach room temperature; at this reduced pressure. The reaction product contained 5.1% nitrogen The above: described non-ash forming. detergents such. as monopolyallgylene. succinirnides according to the in-. vention may be incorporated into lubricating; QilS in; amounts between 0.1 and, 10% by/weight, preferably between 0.25% and 5%; by:v weight, basedonthe weight of the oil.

The other; essentialadditives are (II)v alkylated bis phenols which are, used in the lubricating oil;compositionsi according; to the invention and; are preferably alkyl derivatives 0f rbist-phenols having the-formula:

carbon atoms and especially 4 carbon atoms. Furthermore, the alkyl groups contained by any particular bisphenol may be the same or different and may also be primary, secondary or tertiary alkyl groups. Bis-phenols containing at least one tertiary alkyl group are particularly preferred.

As examples of the alkylated bis-phenols which may be used according to the invention there are mentioned bis 3-ethyl-4-hydroxyphenyl) disulfide,

bis 3-methyl-4-propyl-5-hydroxyphenyl) disulfide,

bis(2-isopropyl-3-butyl-5-hydroxyphenyl)selenide,

2:2'-diethyl-3 -tertiary butyl-4"4-dihydroxy diphenyl selenide,

bis 1.2 2 6-di-tertiary butyl-4-hydroxyphenyl) thiaethane,

bis 1.2 (2 -di-isopropyl-3 -hydroxyphenyl) thiaethane,

bis( 3 :S-di-tertiary bntyl-4-hydroxyphenyl)sulfide,

2 4-di-isobutyl-3 -hydroxybenzyl-2 :4-dipropyl- 3-hydroxybenzyl sulfide,

bis 1.2(3-octyl-5-tertiary butyl-4-hydroxyphenyl)ethane,

bis 1.1 (2 6-di-isopropyl-4-hydroxyphenyl ethane,

1.2-bis(2:4-di-tertiary pentyl-3-hydroxyphenyl) propane,

bis 2.2(4 S-di-tertiary butyl-Z-hydroxyphenyl)propane,

bis Z-tertiary butyl-5-isopentyl-4-hydroxyphenyl) amine,

bis 3 :5 -dibutyl-4-hydroxyphenyl ether,

bis (2 6-dipropyl-4-hydroxyphenyl) ether.

Examples of alkylated bis-phenols having a sulfur bridge are his (2 5-dipentyl-4-hydroxyphenyl sulfide,

bis(2:5-dihexyl-3-hydroxyphenyl)sulfide,

bis 2-methyl-5-tertiary butyl-4-hydroxyphenyl sulfide,

bis(2-methyl-5-tertiary butyl-6-hydroxyphenyl)sulfide and particularly bis (Fl-tertiary butyl-5-methyl-2- hydroxyphenyl) sulfide.

Examples of alkylated bis-phenols having a methylene bridge are bis (2 3-di-tertiary butyl-4-hydroxyphenyl) methane,

bis (2 S-di-tertiary butyl-4-hydroxyphenyl)methane,

bis (2 6-di-tertiary butyl-4-hydroxyphenyl methane,

bis 3 :S-di-tertiary octyl-4-hydroxyphenyl methane,

bis(3-tertiary butyl-S-tertiary octyl-4-hydroxyphenyl) methane, and especially 1 bis (3 S-di-tertiary butyl-4-hydroxyphenyl) methane.

The alkylated bis-phenol may be prepared by any of the methods known in the art of bis-phenol manufacture, for example, by selecting the appropriate alkylated phenols as starting materials and condensing them to-' gether by any of the established methods.

The bis-phenols may be used in amounts of from 0.1% to 5%, preferably from 0.5% to 1% by weight.

The lubricating oil compositions according to the invention may be further improved by addition of small amounts of a third additive which are (IH) metal-free organic phosphorus-containing compounds such as alkyl, cycloalkyl, alkaryl, aralkyl, and aryl phosphites, phosphates, phosphonates, and their thio-derivatives, such as C alkyl phosphites, e.g. diand tributyl, octyl, lauryl, stearyl, cyclohexyl, benzyl, cresyl, phenyl phosphites or phosphates, as well as their thio-derivatives: P sg-terpene reaction product, P S -pine oil reaction product and metal salts thereof such as sodium, potassium, calcium, or barium salts of P S -terpene reaction product; dibutyl methanephosphonate, dibutyl trichloromethanephosphonate, dibutyl monochloromethanephosphonate, dibutyl chlorobenzenephosphonate, dibutyl monochloromethanephosphonate, dibutyl chlorobenzenephosphonate and the like. The esters of pentavalent phosphorus acids such as diphenyl, dicresyl, triphenyl, tricresyl, trilauryl and tristearyl phosphate, P S -terpene reaction products and mixtures thereof are preferred.

The phosphorus compounds may be used in amounts of from 0.01% to 5%, preferably from 0.1% to 1% by weight.

Lubricating oils which can be used as base oils for the lubricating oil compositions according to the invention include a Wide variety of lubricating oils,

such as naphthenic base, paraflin bases, and mixing. base lubricating oils, other hydrocarbon lubricants, e.g.,

lubricating oils derived from coal products, and synthetic oils, e.g., alkylene polymers (such as polymers 'of propylene, butylene, etc., and the mixtures thereof), alkylene oxide-type polymers (e.g. alkylene oxide polymers preparedby polymerizing the alkylene oxide, e.g. propylene oxide, etc., in the presence of water or alcohols, e.g. ethyl alcohol), dicarboxylic acid esters (e.g. those Which are prepared by esterifying such dicarboxylic acids as adipic acid, azelaic acid, suberic acid, sebacic acid, succinic acid, fumaric acid, maleic acid, etc., with alcohols, such as butyl alcohol, hexyl alcohol, 2- ethylhexyl alcohol, dodecyl alcohol, etc.) liquid esters of acids of phosphorus, alkyl benzenes, polyphenyls (e.g. biphenyls and terphenyls), alkyl biphenyl ethers, polymers of silicon (e.g. tetraethyl silicate), tetra-isopropyl silicates, tetra (4-methyl-2-tetraethyl) silicate, hexyl (4- methyl-Z-pentoxy) disiloxane, poly(methyl) silox-ane, an poly(methylphenyl) siloxane.

The above base oils may be used individually or in combinations thereof, Wherever miscible or Wherever made so by the use of mutual solvents.

The following non-ash lubricating compositions are representative of the invention.

Composition A. Percent, Example I additive 2 Bis(3,5-ditert-butyl-4-hydroxyphenyl) methane 0.75 Mineral lubricating oil (SAE 20) Balance Composition B:

Example II additive 2 Bis (3 ,5 -ditert-butyl-4-hydroxyphenyl) methane 0.75 Mineral lubricating oil (SAE 20) Balance Composition C: Example III additive 2 Bis(3,5-ditert-butyl-4-hydroxyphenyl) methane 0.75 Mineral lubricating oil (SAE 20) Balance Composition D:

Example IV additive 2 Bis(3,5-ditert-butyl-4-hydroxyphenyl) r methane 0.75,

Mineral lubricating oil (SAE 20W-30) Balance Composition E:

Example I additive 2 Bis 3 ,5 -ditert-butyl-4-hydroxyphenyl) methane 0.75 Tricresylphosphate 0.5 Mineral lubricating oil (SAE 20) Balance Composition F:

Example IV additive 1 2 Bis(3,5-ditert-butyl-4-hydroxyphenyl) methane 0.75 Tricresylphosphate 0.5 Mineral lubricating oil (SAE 20) Balance Composition G: I I

Example IV additive 1 Bis(3,5-ditert-butyl-4 hydroxyphenyl) methane 0.75 Tricresylphosphate 0.5 Mineral lubricating oil (SAE 20) Balance Composition H:

Example VIII 3 Bis (3 ,5 -ditert-butyl-4-hydroxyphenyl) methane 0.75 Tricresylphosphate 0.80 Dicresyl 0.04

Mineral lubricating oil (SAE 10W-30) Balance Tests Hot-plate test.A plate 12 inches long and 2.5 inches wide is provided with troughs along its width at top and bottom for the distribution and collection of oil. The plate is. heated. to and maintained at a temperature of 270 C. and, 500 grns. of lubricating oil is circulated over the plate for six hours maintaining a flow rate of approxi mately 6.5 mls. per minute. After the test the deposits are scraped from. the. plate, and washed into a sintered glass filter with petroleum ether. After thorough Washing with petroleum. ether (boiling range 60 C. to 80 C.) thedeposit is dried, at 100 C; and weighfid after cooling.

This. hot-plate test was carried out on a variety of lubricating. oil compositions "based on an SAE 20 lubricating oil,; and. the resultsv are tabulated below.

Enginatest-A BMC SeriesB gasoline engineis bench testrun over-34- of thefollowing 4-hour cycles.

Period Duration Speed, rpm. B. hp.

1 1 hour 2,000 2-.-- mins... 3,800 17. 5. 3; 1 hour 600 Idling 4 15 mins... 3, 800 17. 5' 5 1 hour..." 600 Idling 6 '30 mins n Shut-down with forecdeooling (Each 4-hour cycle is approximately equivalentto 56 road, miles.) The. jacket temperature of the engine is controlled at 45'' C. and the coolant fiowto the sump jacket is controlled so that the sump temperature is 60- C. during period, 1- of; the cycle.

The engine is charged with 6 /i pints of testoil and is ,checked'atthe endof'every 6th cycle; and, if necessary, more test oil is' added; to bring'the oil level back to the initialsetting; No'oil'check or addition isrnade-atthe end of the 30th cycle.

After the 34'4=hou rcycles an examination is-made of the rocker cover, timingcover and side covers sump. A visual rating from O-to 10 is made; 10 beirigperfectly clean and- 0' beingcompletely covered-by sludge, over inchthick.

Various lubricating oils, including a lubricating-enaccording to' the invention were tested by'this' procedure and the results are given in TableII;

Other additives may also be incorporated into the lubricating composition according to the invention, for example antiscufiing agents, anti-foaming agents, erg. silicone polymers; viscosity index improvers, for example polymeric acrylic esters; extreme pressure additive, for example dibenzyl disulfide; rust inhibitors, for example sorbitanmonooleates or butyl. stearate, oiliness agents, for example acidless tallow, oleic acid and the like.

I claim as my invention:

1. A lubricating composition consisting. essentially of a major amount of lubricating oil and from about 0.1% to about 10% by weight of (I). an oil-soluble succinimide of a mono-(C olefinic' hydrocarbyl)succinic anhydride and a poly,(C, alkylene)polyarnine having at least 2 amino groups in the molecule, (11-) from about 0.1% to about 5% by weight of bis( dialkyl' hydroxy phenyl)methane and (III) from about 0.01% to about 5% by Weight of tri(:rnonoaryl)phosphate.

2. A lubricating oil composition consisting essentially of a major amount of mineral lubricating oil and from about 025%. to about 5% by Weight of (I) an oilsoluble succinimide of mono-( polyisobutylene) succinic anhydride and. tetraethylene pentamine, the polyisobutylene radical having a molecular Weight of from 500 to, 3000, (II) from about 0.5% to. about 1% of bis(dialkylhydroxyphenyl)methane and (111) from about 0.01% to about 5% by weight of tricresyl phosphate.

3. A lubricating oil composition consisting essentially of a major amount of mineral lubricating oil and from about 0.25% to about 5% by weight of (I) an oilsoluble. succinimideof, mono-(polyisobutylene) succinic anhydride and tetraethylene pentamine, the polyisobutylene radical having a molecular weight of from 500 to 3000, (II) from about 0.5% to about 1% of his (3,5- ditert-hutyl-4=hydroxyphenyl)methane and (III) from about 0.01% to about 5% by'weight of tricresyl phos= phate.

References Cited UNITED. STATES. PATENTS 2,5 60,542 7/ 1951. Bartleson et a1. 44"69 2,807,653 9/ 1957 Filbey et al 252--52 3,018,247 1/1962 Anderson et' al 25251-.5 3,018,250 1/ 1962 Anderson et .al. 2525'1.5 3,018,291 171962 Anderson et a1. ,.252.-5:l'.5 2,157,873 5 /1939 van Peski et a1. 252.--49;8 3,131,150 4/ 1964. Stuart et'al 252--5,1.5 3,172,892 3/1965 Le S'ueret a1. 252-51.5

DANIEL E. WYMAN, Primary; Examiner.

ALPHONSOD'; SULLIVAN, Examiner.

I.- R. SEI-LER, L. G. XIARHOS, Assistant'Examinern 

1. A LUBRICATING COMPOSITION CONSISTING ESSENTIALLY OF A MAJOR AMOUNT OF LUBRICATING OIL AND FROM ABOUT 0.1% TO ABOUT 10% BY WEIGHT OF (1) AN OIL-SOLUBLE SUCCINIMIDE OF A MONO-(C20-300 OLEFINIC HYDROCARBYL) SUCCINIC ANHYDRIDE AND A POLY (C1-6 ALKYLENE) POLYAMINE HAVING AT LEAST 2 AMINO GROUPS IN THE MOLECULE, (11) FROM ABOUT 0.1% TO ABOUT 5% BY WEIGHT OF BIS (DIALKYL HYDROXY PHENYL) METHANE AND (111) FROM ABOUT 0.01% TO ABOUT 5% BY WEIGHT OF TRI (MONOARYL) PHOSPHATE. 